title: Comparison of ultrasound-guided supraclavicular block according to the various volumes of local anesthetic.
abstract: BACKGROUND
  The ultrasound guidance in regional nerve blocks has recently been introduced and gaining popularity. Ultrasound-guided supraclavicular block has many advantages including the higher success rate, faster onset time, and fewer complications. The aim of this study was to examine the clinical data according to the varied volume of local anesthetics in the ultrasound-guided supraclavicular block.
  
  
  METHODS
  ONE HUNDRED TWENTY PATIENTS WERE RANDOMIZED INTO FOUR GROUPS, ACCORDING TO THE LOCAL ANESTHETIC VOLUME USED: Group 35 (n = 30), Group 30 (n = 30), Group 25 (n = 30), and Group 20 (n = 30). Supraclavicular blocks were performed with 1% mepivacaine 35 ml, 30 ml, 25 ml, and 20 ml, respectively. The success rate, onset time, and complications were checked and evaluated.
  
  
  RESULTS
  The success rate (66.7%) was lower in Group 20 than that of Group 35 (96.7%) (P < 0.05). The average onset times of Group 35, Group 30, Group 25, and Group 20 were 14.3 ± 6.9 min, 13.6 ± 4.5 min, 16.7 ± 4.6 min, and 16.5 ± 3.7 min, respectively. There were no significant differences. Horner's syndrome was higher in Group 35 (P < 0.05).
  
  
  CONCLUSIONS
  In conclusion, we achieved 90% success rate with 30 ml of 1% mepivacaine. Therefore, we suggest 30 ml of local anesthetic volume for ultrasound-guided supraclavicular block.
authors.affiliation: Department of Anesthesiology and Pain Medicine, College of Medicine, Dankook University, Cheonan, Korea.
authors.forename: Dae Geun
authors.initials: DG
authors.lastname: Jeon
authors.forename: Seok Kon
authors.initials: SK
authors.lastname: Kim
authors.forename: Bong Jin
authors.initials: BJ
authors.lastname: Kang
authors.forename: Min A
authors.initials: MA
authors.lastname: Kwon
authors.forename: Jae Gyok
authors.initials: JG
authors.lastname: Song
authors.forename: Soo Mi
authors.initials: SM
authors.lastname: Jeon
keywords: Regional nerve blocks; Supraclavicular block; Ultrasound guidance